The Last House on the Left

The Last House on the Left is a 1972 horror film. It was Wes Craven's feature film debut.

1000 Misspent Hours opens with this:

If there is any one movie that can be taken to symbolize the trend toward utterly unapologetic viciousness in the horror films of the 1970’s, Wes Craven’s The Last House on the Left is probably it.

and calls it

the movie that proves that in the right hands, torture, rape, murder, and relentless psychological brutalization can in fact be kind of boring.

Moria says it

inspired a genre of films that this author has nicknamed the Backwoods Brutality cycle

CinemaBlend.com reports that

this film has some good points, but it cannot counter-act with the overall incompetence of the whole film.

and suggests skipping it entirely in favor of

the beautifully filmed Ingmar Bergman original, The Virgin Spring, starring a young Max Von Sydow, based on an old Scandinavian wives’ tale. Or if you’d prefer something just a little sleazier, I would suggest Aldo Lado’s Last House Italian rip-off, The Night Train Murders.

Embedding is disabled, but the movie can be seen on youtube in 9 parts. Part 1 is here. I'm skipping this one; I have the Criterion edition of The Virgin Spring in the stack waiting its turn.